This is a continuation of a cooperative inter-institutional study of cancer in children utilizing multi-disciplinary approach to treatment of those types of cancer which are suited to scientific analysis in a reasonable period of time. The studies are designed to provide answers to questions concerning optimum management; and at the same time provide the individual institutions with the added strengths to provide its community with a referral center for childhood cancer. At the time of writing, there are eleven active protocols dealing with leukemia and 19 including Phase II studies dealing with solid tumors. The principle protocol for ALL/AUL is designed to determine the relative importance of front-end factors in prognosis with randomized increased therapy during maintenance for those with known poor prognostic findings. The present AML protocol is an effort to improve survival, duration of remission in childhood AML by combining the two best therapies from CCSG 241 and CCSG 102. Specific protocols currently being used are for localized and metastatic neuroblastoma, Histiocytosis, Retinoblastoma unilateral and extraocular, brain tumors, hepatoma osteogenic sarcomas, non-Hodgkins lymphoma and ovarian tumors. On an intergroup basis, there are active protocols for Rhabdomyosarcoma, Ewings, both non-metastatic and metastatic, Hodgkins disease and Wilm's tumor. Protocols being formulated and finalized are for previously treated and untreated metastatic neuroblastomas, bilateral retinoblastoma, Histiocytosis and pineal region germinomas. In addition, on-going Phase II protocols utilizes a succession or combination of new therapeutic agents such as cyclocytidine. Vindesine, VM 26, 5FU, Galactitol and AZapicyl. Heromukylemelamine, the newest agent, is presently being formulated.